Array predicates are a not-so-well-known feature introduced with the .NET Framework 2.0 that let you retrieve specific items or perform operations on all items of an array. For example, a quick way to ensure that none of the parameters passed to a function are empty or null is to use the Any predicate.
As an example, assume a method takes four string parameters. Obviously, one way to determine if any of them are empty is to iterate through the parameters testing each one in turn, but a better method is to use the Any operator. Here's an example:
//gather all the input values.
string[] inputValues = {databaseKey, query, databaseType, password};
//check if the arguments are empty.
if (IsEmpty(inputValues))
throw new ArgumentException("All values are required.");
//Function to check if the parameter array has any empty values.
private static bool IsEmpty(string[] values)
{
return (values.Any(value => string.IsNullOrEmpty(value.Trim())));
}
Check out other predicate operations
described here.
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